1. Field of the Invention
The invention relates in general to a card, and more particularly to a flexible card with display function.
2. Description of the Related Art
With the progress of the technology, many transaction and payment ways have been gradually replaced by the conventional integrated circuit (IC) card, such as a credit card, a debit card, a telephone card, a bus card, a metro stored-value card, or the like. The currently available IC cards may be classified into cards with a contact-type interface, a contactless-type interface and hybrid interfaces according to the communication interface.
The cards with the contact-type interfaces may be classified into a smart card and a memory card. The smart card has a control mechanism function and includes an 8-bit, 16-bit or 32-bit microprocessor with the encryption processing of DES, RSA or the like. The memory card includes a memory, such as a read only memory (ROM) or a non-volatile memory, having the memory capacity of 4K, 8K, 16K, . . . , or 1 M bytes.
The cards with the contactless-type interfaces may be classified into A, B and Felica types, wherein A and B types pertain to the proximity ISO 14443 standard, while the Felica type pertains to the standard of Sony Company, and the communication distances thereof range from 0 to 10 cm. The hybrid cards have the contact-type and contactless-type interfaces combined together, and are usually classified into a single chip card and a multi-chip card.
FIG. 1 (Prior Art) is a schematic illustration showing a conventional IC card 1 with display function. As shown in FIG. 1, the communication interface can be either a contactless type RF (radio frequency) interface or a contact-type communication interface, and the driving power source required therein can be a contactless type communication interface or a contact-type communication interface depending on the option of pattern. One can obtain the power source by making use of the following methods:
1. Contactless Type Communication Interface:
Non-contact type communication interface has an antenna 22 provided inside the IC of the contactless type RF interface to perform RF decryption through a communication interface 23 for the RF signals and coupling signals received from an external card reader. On the other hand, the coupling signal generates direct current to supply the internally required voltage through a rectifier/voltage regulator 27.
2. Contact-Type Communication Interface:
The contact-type communication interface has the IC 32 of a contact-type IC card perform decryption to be read in by the microprocessor 24 after the communication interface 23 has received the digital series signals of the external card reader. In the mean time, the external card reader also supplies direct current for internal usage through the contact-type interface.
The working flow chart of the IC card with display panel but without batteries of the invention is as follows:
The microprocessor 24, after receiving the signals from the communication interface 23, can store data in an EEPROM 28. The microprocessor 24 can also convert the data into the driving signals of the display panel 21 through the display driver 25 for the users to look up. The microprocessor 24 can also transmit the response signals to the antenna for the external card reader through the communication interface 23.
The charge-pump 26 converts the current source generated by the rectifier/voltage regulator 27 into a relatively higher voltage for the display driver 25 to convert into driving signals of the display panel 21.
In this way, the communication interface 23, after receiving the external data, can firstly decrypt and decode the data and display them on the display panel 21 for users to look up the data and their content. Since the display panel 21 employed by the invention is the one with bistable function having the characteristic that once the data are displayed, no persistent power supply for the display panel 21 is needed, thereby, the displayed data will be preserved persistently. In other word, not until the next time when the display panel 21 is driven again, and the displayed content or the updated data are changed, the data displayed on it will not disappear.
Moreover, the IC of the above-mentioned contactless type RF IC card (RFIC) 31 and the Contact Smart IC 32 are the Smart ICs that circulate in the market. The invention can easily make the market-circulated Smart IC (contact-type, contactless type, or dual interface type IC) upgrade their level to become display-type IC cards without batteries by adding elements such that their commands and ways of adding confidential means are compatible to those market-circulated Smart IC.
However, the conventional IC card 1 tends to be intruded by a hacker. The hacker can access the important data of the non-volatile readable memory 28 via the communication interface 23 and the microprocessor 24 so that the security of the conventional IC card is seriously affected. In addition, the conventional IC card 1 cannot withstand the curving, and the convenience in use is significantly deteriorated.